Here is my take at building a deck with the "Gunkan" archetype, which is often also referred to as "Suship". In my opinion, the deck is a solid starting point for new players since it takes an easy concept, being the focus on "Gunkan Suship Shari", to build the entire deck. The idea is to Xyz-spam as much monsters as possible, with the Extra Deck featuring a colorful selection of effects to use, and win the game via beatdown.
For further information about the deck and the archetype in general, feel free to visit my "Gunkan" Archetype Analysis on Cubic Creativity.